Belt-centering device



Jan. 2, 1945. G. -F. DODGE BELT CENTERINIG'DEVICE Filed Aug 10, 1943/NVENTO/ Goveoon F DODGE,

Patented Jan. 2, 1945 BELT-CENTERING DEVICE Gordon F. Dodge, Columbus,Ohio, assignor to The Jeffrey Manufacturing Company, a corporation ofOhio Application August 10, 1943; Serial No. 498,090 I 6 Claims.

This invention relates to a belt centering or automatic training device.

An object of the invention is to provide an imf proved automatic beltcentering or trainingdevice particularly for the return run of aconveyor belt which is operable automatically for reverse directions oftravel of the belt.

Other objects of the invention will appear hereinafter, the novelfeatures and combinations being set forth in the appended claims.

In the accompanying drawing,

Fig. 1 is a transverse sectional view of a conveyor including the beltcentering device of my invention;

Fig. 2 is a side elevational view of the conveyor of Fig. 1; g

Fig. 3 is an enlarged side viewof the belt con tering device of myinvention shown in its operating position;

Fig, 4 is a further enlarged end view of the device of my inventionshowing particularly the means for pivotally suspending said beltcentering device on a horizontal axis, the. parts being shown in anon-belt conveying position; v

Fig. 5 is a view taken on the line 5-5 of Fig. 4, looking in thedirection of the arrows, some of the associated parts being shown indotted lines;

Fig.- 6 is an enlarged sectional view taken'on the line 6--5 of Fig. 1,looking in the direction of the arrows; and Y.

Fig. 7 is an enlarged sectional view taken on the line 'I'! of Fig. 6,looking in thedirection of the arrows.

Referring to the accompanying drawing, there is seen a conveyorincluding a main frame I 0 formed of spaced channel members across thetops of which are spaced troughing idlers II which support the upper runof a conveyor belt I2v As illustrated, the lower run of the belt I2 isflat rather than being troughed and at intervals it is mounted upon abelt centering or training device I3 comprising my invention. I

The belt centering device I3 includes a pair of spaced brackets 14, I4which' are of similar structure and which are bolted or otherwiseattached to the bottom flanges of the channels of main frame I0. Each ofthe brackets I4 is in the form of a yoke with wings which provideforattachment to the frame member I 0 by virtue of spaced bolts I5.

The bottom edge of each bracket I4 forms a narrow semi-knife edgedbearing-surface I 6 along which is adapted to roll a short piece of pipeor cylinder I I which is rigidly attached to and forms an effectivepivotal member of an end bracket I8, there being two such end bracketsI8 rigidly attached to the opposite ends of a pipe' I9 which togetherwith brackets l8 and pipes I I may be considered as constituting themain frame of the belt centering device I3. I

Each of the stationary brackets I4 is provided with a screw which isthreaded through the bottom flange of said bracket and is provided witha pointed nose 2| which extends loosely through a hole in the bottom ofthe pipe [1. As illustrated, the short pipe I! is rigidly attached tothe bracket I8 by a set screw 22, and brackets I8 are attached to mainframe pipe I9 by a pair of set screws 23.

From the description so far given and from the illustration in thedrawing it is evident that the main frame I'I, I8, I9 may swing about ahorizontal axis which is along the bottoms of the ment while the shortpipes I! roll on the bearing surfaceIB. This swinging movement may be ineither .of ,two reverse directions, that is, either I clockwise orcounter-clockwise, and in Fig. 3 of bracket 25.

the drawing I have illustrated the swinging movement in the maximumclockwise direction, this maximum movement in both directions beingdeterminable by a pair of spaced stops 24, 24 formed on opposite sidesof the opening in bracket I4 through which the short pipe I! extends.

Adjacent its center an upstanding bracket 25 is rigidly attached to themain frame pipe I9. Since the base of the bracket 25 is a cylinder whichsurrounds said pipe. I9 it is preferably rigidly attached thereto as byset screws or the like.

It may be stated that When the end brackets I 8 are in the uprightposition, for example, as illustrated in Fig. 4 of the drawing, thebracket 25 will also be in the upright position as illustrated in Fig. 6of the drawing.

At its top the bracket 25 includes a removable cap 26 which is removablyattached by screws 21. The cap 26 is half of a generally'cylindricalportion of the bracket 25, through which cylindrical portion there is abore 28 through which a non-rotary shaft 29 provided with a non-rotaryshaft housing 30 extends. The shaft 29 and housing 30 are preferablyrigidly connected together and. consequently in effect constitute asingle part and may be considered as a single Shaft. t v

The shaft 29 and housing 30 are pivotally -mounted about a generallyupright axis by means of pivot pins 3I, the inner ends of'which arethreadedinto the housing 30 and the outer ends of which are journaled inappropriate bores in the upper cylindrical portion of bracket 25.

The pins 3| are provided with central lubrication bores 32, and acommunicating lubrication bore 33 extends to a grease gun fitting 34on'the on opposite ends the shaft 29 is provided with a pair ofindependently rotatable idler rollers 35, 35 preferably mounted-onspaced anti-friction roller bearings. The shaft 29 and housing 30constitute in effect a swinging frame or support by which the idlerrollers 35 are swingabiy mounted on the main frame l9 etc; about agenerallyupr'igh't axis,"but, as hereinafter pointed out, in operationthis axis will swing in a plane parallel with the direction of movementof the conveyor belt l2.

When the conveyor belt I2 is stationary, the axis of the pivot of swingpins 3| will'be vertical and the parts will be in the positionsillustrated in Figs. 2 and 4 of the drawing. That is, atransverse planewith respect to the longitudinal axis of the conveyor which passesthrough the axis of the main frame pipe l9 and the axis of the pins 3!,will be vertical. If now the conveyor is .placed in operation and .thelower run of the belt .I 2 travels in the..direction'illustrated in Fig.3 of the drawing, the mainframe ['9 will pivot about its horizontal axisland the cylinders I! will roll on the bearing surfaces [6 until suchcylinders l -1 engage stops 2'4,'-.whereupon the axis of the pins 3|will be inclined to the vertica'lin the direction of travel of the'lowerrun oft'he'be'lt l2.

The swing frame or support .constituted'by'the shaft 29 and housing 30will be free to swing about this inclined upright :ax'is. As aconsequence of this .arrangement the return .run of the belt 12 .intraveling .over the rollers '35 will be automatically trained orcentered since the action ment of my invention, what I desire to secureby Letters Patent of the United States is:

1. A belt centering device including a stationary frame, a main framepivotally mounted of .a pair .of idler :rollers mounted on an inclinedaxishas :an automatic guiding ortraining action, as is well understoodin this .art. j

Furthermore, inthemost complete embodiment of my invention, greaterefficiency is realized by employing tworoll'ers 35instead o'f'asingleroller since this "increases ithersensitivity of'the device. 'So'long .as the return run of thebelt [2T5 prop erly tcentered, .theswinging fframe including the shaft -29 and housing, 30 will 'haveitsaxis substantially at right angles'to the directionof travel of saidreturn run o'f'be'lt l2. Th swinging movement of this swinging frame,:30, is, of course, limited by the size of "the opening 28, and inpractice such swinging frame is preferably free t swing from 2 degreesto 5 degrees on either side of central or normal position.

It :is obvious that 'if the direction :of travel of the "belt 12 isreversed, the "belt centering device 13 Wl11 automatically swing to'reverse'pos'ition from that "illustrated 'in'Fig. 3 so that -the axisof the pins 3| is now inclined to the "other side of thetransverse-vertical plane and again "the device operates tomaintain saidreturn run of the belt r2 .inproperalignment.

It may be "further pointed out that the 'horizontal pivot axis ofthemain "frame l1, l8, I9 is at the: centers of the pipes I"! and movesin a plane parallel with surfaces -16. Also the center of gravity of thedevice "13 is preferably substantially along'this plane. i As aconsequence, in the absence of an "operating force such as provided bythe movement "of belt l2, the device l3 will stay in any'pos-ition "towhich'it is adjusted. This feature aidsin'the ease of automaticreversability of the device F3 for reverse travel of the belt [2 sincepractically no work is "involved in moving it.

While the deviceas 'illustratedis applied to the return run of a belt ofa conveyor, it is obvious that it may be-employedforthe :carry'ing runparticularly if through "the'carrying run the 'belt isimaintainedt-fiatratherthan troughed.

Obviously those skilled :in the art may make variousximprovements in thedetails and arrangement of parts without departing from :the spirit andscope of the invention as defined by the claims hereto appended, and SIthere'fore'wish. not

on said stationary frame for pivotal movement about a horizontalaxis, aswinging support swingably mounted at its center on said main frameabout an upright axis which may swing to opposite sides of .a verticalplane through the pivotal axis of said main frame, and separate rollersmountedon said swinging support on opposite sides of said upright axis.

'2. A belt centering deviceincluding astationary frame, a main framepivotally mounted on said stationary frame for pivotal movement about ahorizontal 'axis, a swinging support swingably mounted at its center onsaid main frame about an upright axis which may swing to opposite sidesof a. vertical plane through the pivotal axis of said main frame, andbelt supporting roller meansmounted on said swinging support.

3. A belt centering device including a stationary frame, a main framepivotally mounted on said stationary frame for pivotalmovement about ahorizontal axis, a swinging support swingably mounted at its center onsaid main frame about an upright axis which may swing to opposite sidesof a vertical plane through the pivotalaxis of saidmain'frame, and"separate rollers'mounted on sai'cl'swinging support on opposite sidesof said upright axis, the center of gravity'of said main frame and partscarried-thereby being substantially at "the pivotal axis of said mainframe.

'4. A belt centering 'device including a stationary frame, a main frame'pivotally mounted on said said mainframe, and'belt'support'ing rollermeans upright :axis which spaced cylindrical roll on bearing surfaces onsaid spaced brackets,

: mounted on said swinging supportfthe center of gravity of saidmainframe and parts carried thereby being substantially at the pivotal axisof said main frame.

5. A belt aligningidler including stationary spaced'brackets, a mainframe extending between said brackets and mounted "thereon for pivotalrolling movement, said main frame including spaced cylindrical bearingmembers adapted to roll on bearing surfaces on said spaced brackets andspaced .oppositely positioned stops therefor on opposite sides of abracket, aipivoted swinging support mounted-on said main frame forswinging movement about a generally upright axis which axis swings with.said main frame, and belt supporting roller means on said pivotedswinging support. y

6. .A belt aligning .idler including stationary 'spacedbrackets, a mainframe extending between said brackets and mounted thereon for pivotalrolling movement, said main frame including bearing members adapted toapivoted swinging support mounted .onsaid main frame .for' swinging.movement about a generally axis swings with said main frame, :and beltsupporting roller means on said pivoted swinging support.

GORDON F. DODGE.

